linux-kernel - [PATCH 02/02] x86_64: Add safe check in a.out loaders and some coding style

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Message-Id: <1379539641-1726-2-git-send-email-geyslan@gmail.com>
Date:	Wed, 18 Sep 2013 18:27:21 -0300
From:	"Geyslan G. Bem" <geyslan@...il.com>
To:	viro@...iv.linux.org.uk, linux-fsdevel@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, "Geyslan G. Bem" <geyslan@...il.com>
Subject: [PATCH 02/02] x86_64: Add safe check in a.out loaders and some coding style

ia32_aout had no safe checks concerning the mmap and f_op in this module.
It's not necessary to verify f_op in the load_aout_library, since the
prior kernel_read/vfs_read function already does.
Coding style and printks fixes.

Tested using qemu, a handcrafted a.out binary and a a.out linked with a
cross-compiled ld.

Signed-off-by: Geyslan G. Bem <geyslan@...il.com>
---
 arch/x86/ia32/ia32_aout.c | 25 ++++++-------------------
 1 file changed, 6 insertions(+), 19 deletions(-)

diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c
index 15a8319..46a0346 100644
--- a/arch/x86/ia32/ia32_aout.c
+++ b/arch/x86/ia32/ia32_aout.c
@@ -24,7 +24,7 @@
 #include <linux/binfmts.h>
 #include <linux/personality.h>
 #include <linux/init.h>
-#include <linux/jiffies.h>
+#include <linux/ratelimit.h>
 
 #include <asm/uaccess.h>
 #include <asm/pgalloc.h>
@@ -346,21 +346,13 @@ static int load_aout_binary(struct linux_binprm *bprm)
 		}
 	} else {
 #ifdef WARN_OLD
-		static unsigned long error_time, error_time2;
 		if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
-		    (N_MAGIC(ex) != NMAGIC) &&
-				time_after(jiffies, error_time2 + 5*HZ)) {
-			printk(KERN_NOTICE "executable not page aligned\n");
-			error_time2 = jiffies;
-		}
+		    (N_MAGIC(ex) != NMAGIC))
+			pr_notice_ratelimited("executable not page aligned\n");
 
-		if ((fd_offset & ~PAGE_MASK) != 0 &&
-			    time_after(jiffies, error_time + 5*HZ)) {
-			printk(KERN_WARNING
-			       "fd_offset is not page aligned. Please convert program: %s\n",
+		if ((fd_offset & ~PAGE_MASK) != 0)
+			pr_warn_ratelimited("fd_offset is not page aligned. Please convert program: %s\n",
 			       bprm->file->f_path.dentry->d_name.name);
-			error_time = jiffies;
-		}
 #endif
 
 		if ((fd_offset & ~PAGE_MASK) != 0) {
@@ -451,13 +443,8 @@ static int load_aout_library(struct file *file)
 
 	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
 #ifdef WARN_OLD
-		static unsigned long error_time;
-		if (time_after(jiffies, error_time + 5*HZ)) {
-			printk(KERN_WARNING
-			       "N_TXTOFF is not page aligned. Please convert library: %s\n",
+		pr_warn_ratelimited("N_TXTOFF is not page aligned. Please convert library: %s\n",
 			       file->f_path.dentry->d_name.name);
-			error_time = jiffies;
-		}
 #endif
 		vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
 
-- 
1.8.4

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